Investigations of wear in journal bearings due to lubricant contamination

Abstract

Journal bearings should ideally function under a hydrodynamic lubrication regime to reduce wear and friction via sliding. Lubricant contamination by particles and moisture is the most prevalent cause of machine wear and failure. Now a day’s machines are required to operate under more challenging conditions like very high temperatures or in a dust polluted environment. These conditions can adversely affect the proper functioning of rotating machine components and could impact the service life in particular journal bearings are prone to the contaminated environment and their performance can be reduced significantly due to moisture, dust particle, wear debris, or due to corrosion caused by water contamination. The present study was carried out to evaluate the cases of foreign ingested particle pollutants and water contamination using vibration monitoring techniques in the journal bearing lubrication system and aims to establish a relationship between contamination and the journal bearing vibration response to achieve an online condition monitoring of the tribological conduct of journal bearing. Besides, cases involving varying sizes and amount of particles and water contamination have been carefully investigated and demonstrated. The vibration responses of the journal bearing are obtained under various working conditions by connecting the accelerometer to the bearing housing. The results showed that in lubricating oil particle size, concentration, and water volume ratios have different degrees of impact on journal bearing performance.